Module: MMTree

Defined in:
lib/mm_tree.rb

Defined Under Namespace

Modules: InstanceMethods

Class Method Summary collapse

Class Method Details

.included(klass) ⇒ Object 



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# File 'lib/mm_tree.rb', line 41

def self.included klass
  klass.class_eval do
    belongs_to :parent, 
               :polymorphic => true, 
               :foreign_key => :parent_id
    
    many :children, 
        :as => :parent, 
        :foreign_key => :parent_id
             
    key :parent_id, ObjectId
    key :parent_type, String
    key :depth, Integer, :default => 0
    
    
    after_create :set_depth
    
    class_eval <<-EOV
      def self.roots
        find(:all, :conditions => {:parent_id=>nil}, :order => "depth")
      end

      def self.root
        find(:first,:conditions => {:parent_id=>nil},:order => "depth")
      end
    EOV
    
    include InstanceMethods
  end
end